refactor: GenericArrayListQueue (#5355)

src/test/java/com/thealgorithms/datastructures/queues/GenericArrayListQueueTest.java

@@ -0,0 +1,55 @@
+package com.thealgorithms.datastructures.queues;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.junit.jupiter.api.Test;
+
+class GenericArrayListQueueTest {
+
+    @Test
+    void testAdd() {
+        GenericArrayListQueue<Integer> queue = new GenericArrayListQueue<>();
+        assertTrue(queue.add(10));
+        assertTrue(queue.add(20));
+    }
+
+    @Test
+    void testPeek() {
+        GenericArrayListQueue<Integer> queue = new GenericArrayListQueue<>();
+        assertNull(queue.peek());
+
+        queue.add(10);
+        queue.add(20);
+
+        assertEquals(10, queue.peek());
+        queue.poll();
+        assertEquals(20, queue.peek());
+    }
+
+    @Test
+    void testPoll() {
+        GenericArrayListQueue<Integer> queue = new GenericArrayListQueue<>();
+        assertNull(queue.poll());
+
+        queue.add(10);
+        queue.add(20);
+
+        assertEquals(10, queue.poll());
+        assertEquals(20, queue.poll());
+        assertNull(queue.poll());
+    }
+
+    @Test
+    void testIsEmpty() {
+        GenericArrayListQueue<Integer> queue = new GenericArrayListQueue<>();
+        assertNull(queue.peek());
+        assertNull(queue.poll());
+
+        queue.add(30);
+        assertEquals(30, queue.peek());
+        assertEquals(30, queue.poll());
+        assertNull(queue.peek());
+    }
+}